Query a nested object after deserialisation xml

Question

When trying a lot of examples of deserialize xml into a object in C#. I manage to get some values of some of the elements. But nested values from recuring nodes Like the ID of level 2 , or the values of level4) are giving me not the values I expected. Do I mis something??

• How to deserialize xml to object
• Deserialization from XML to List Object

The importing part is not a problem (I think)

The demo xml

<?xml version="1.0"?>
<root>
  <b>value1</b>
  <level1>
    <level2>
      <id>1</id>
      <level3>
        <level4>Value 1.1</level4>
        <level4>Value 1.2</level4>
      </level3>
     </level2>
     <level2>
      <id>2</id>
      <level3>
        <level4>Value 2.1</level4>
        <level4>Value 2.2</level4>
      </level3>
    </level2>
  </level1>
</root>

the objects

[XmlRoot(ElementName = "root")]
public class root 
{
    [XmlElement("b")]
    public string b { get; set; }

    [XmlElement("level1")]
    public level1 level1 { get; set; }
}

public class level1
{
    [XmlElement("level2")]
    public List<level2> level2 { get; set; }
}

public class level2
{
    [XmlElement("id")]
    public int id { get; set; }

    [XmlElement("level3")]
    public level3 level3 { get; set; }
}

public class level3
{
    [XmlElement("level4")]
    public List<string> level4 { get; set; }
    //OR 
    //public string[] level4 { get; set; }
}

A parsehelper

 static class ParseHelpers
 {
    public static Stream ToStream(this string @this)
    {
        var stream = new MemoryStream();
        var writer = new StreamWriter(stream);
        writer.Write(@this);
        writer.Flush();
        stream.Position = 0;
        return stream;
    }

    public static T ParseXML<T>(this string @this) where T : class
    {
        var reader = XmlReader.Create(@this.Trim().ToStream()
           , new XmlReaderSettings() 
           { 
               ConformanceLevel = ConformanceLevel.Document 
           });
        return new XmlSerializer(typeof(T)).Deserialize(reader) as T;
    }
 }

Deserialize

string filepath = @"C:\xml.xml";
string xml = File.ReadAllText(filepath);
var a = xml.ParseXML<root>();

Here some of the things I tried

Console.WriteLine(a.b);
// this is working :
// return
// value1

Console.WriteLine(a.level1.level2);
// expected error 
// System.Collections.Generic.List`1[Project.level2]

Console.WriteLine(a.level1.level2[0].id.ToString());
// System.ArgumentOutOfRangeException: 'Index was out of range.

foreach(var item in (a.level1.level2))
{
    Console.WriteLine(item.id.ToString());
}
// return
// 0
// 0

List<level2> l1 = a.level1.level2;

foreach (var item in (l1))
{
    Console.WriteLine(item.id.ToString());
}
// return
// 0
// 0

Answer 1

Based on @vitalygolub suggestion to change the properties .I used the edit => paste special (paste XML as Classes) for a new setup of objects (i should have done that first). After some cleanup, I got a new set of objects. ( I do not completely gasp the abstract complexity of the generated objects), but it works exactly as I want.

[System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true)]
[System.Xml.Serialization.XmlRootAttribute(Namespace = "", IsNullable = true)]
public partial class root
{
    public string b { get; set; }

    [System.Xml.Serialization.XmlArrayItemAttribute("level2", IsNullable = true)]
    public rootLevel2[] level1 { get; set; }
}

[System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true)]
public partial class rootLevel2
{
    public string id { get; set; }

    [System.Xml.Serialization.XmlArrayItemAttribute("level4", IsNullable = true)]
    public string[] level3 { get; set; }
}

Now I can navigate thru the objects.

foreach(var item_l2 in a.level1)
{
    Console.WriteLine(item_l2.id);

    foreach (var Item_l4 in item_l2.level3)
    {
        Console.WriteLine(Item_l4);
    } 
}

Answer 2

Try following :

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml;
using System.Xml.Linq;


namespace ConsoleApplication19
{
    class Program
    {
        const string FILENAME = @"c:\temp\test.xml";
        static void Main(string[] args)
        {
            new Level(FILENAME);

        }
    }
    public class Level
    {
        public static Level root = new Level();

        public string name { get; set; }
        public int? id { get; set; }
        public string text { get; set; }
        public List<Level> children { get; set; }

        public Level() { }
        public Level(string filename)
        {
            XDocument doc = XDocument.Load(filename);
            XElement xRoot = doc.Root;

            ParseTree(xRoot, root);

        }

        public void ParseTree(XElement xParent, Level parent)
        {
            parent.id = (int?)xParent.Element("id");
            parent.text = xParent.NextNode  != null ? xParent.Value : "";
            foreach(XElement level in xParent.Elements().Where(x => x.Name.LocalName.StartsWith("level")))
            {
                Level child = new Level();
                if(parent.children == null) parent.children = new List<Level>();
                parent.children.Add(child);
                ParseTree(level, child);
            }
        }


    }

}